/**
 * 
 */
package com.iwords.utils;

import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.util.logging.Level;
import java.util.logging.Logger;

/**
 * @author       BOLIN.HBC 
 * @time         2011-3-12    
 * @description  Md5杈呭姪绫�      
 */
public class Md5 {

    static MessageDigest md5 = null;

	static {
		try {
			md5 = MessageDigest.getInstance("MD5");
		} catch (NoSuchAlgorithmException ex) {
			Logger.getLogger(Md5.class.getName()).log(Level.SEVERE, null, ex);
		}
	}

	/** md5绠楁硶 */
	public static String compute(String value) {

		if (value == null || value.trim().length() == 0) {
			return "";
		}
		char[] charArray = value.toCharArray();

		byte[] byteArray = new byte[charArray.length];

		for (int i = 0; i < charArray.length; i++) {
			byteArray[i] = (byte) charArray[i];

		}
		byte[] md5Bytes = md5.digest(byteArray);

		StringBuilder hexValue = new StringBuilder();

		for (int i = 0; i < md5Bytes.length; i++) {
			int val = ((int) md5Bytes[i]) & 0xff;
			if (val < 16) {
				hexValue.append("0");

			}
			hexValue.append(Integer.toHexString(val));
		}

		return hexValue.toString();
	}
 
}
